Mercury is a useful material to use in a manometer because of its high density . This means that a much shorter column is needed compared to water. For instance, the pressure represented by a column of 100 mm of water is just under 7.4 mm of mercury (mmHg).
Why mercury is widely used for the liquid in the U-tube manometer instead of using water?
Mercury has high density and low length is essential for pressure measuring . Its high density helps to make small manometers. It does not evaporate like water would, and its lower freezing point means it will not freeze up at 0 deg C. Simply it has compactness, visibility and stability.
Why is mercury used in U tube manometer?
Mercury can be used because it has a high density and so the manometer size is minimised . ... Compared to water, a much smaller column of mercury is needed to measure pressure. The common types of manometer are the U-tube, the Well and the Inclined manometer.
How does mercury manometer work?
The liquid mercury is equalized in the two sides of the tube at atmospheric pressure . When the gas is added, it will exert pressure on the mercury on the other side. If the pressure of the gas is equal to atmospheric pressure the mercury will remain at the same levels on both sides.
Why is mercury used in pressure gauges?
As the only metal that is liquid at room temperature, mercury expands and contracts evenly with temperature and pressure changes . These characteristics have made mercury useful in devices used for measuring temperature and pressure, including the following: Barometers measure atmospheric pressure.
Why is it better to use water than mercury in a manometer?
The relationship between pressure and depth is exploited in manometers (or barometers) that measure pressure. ... A barometer using water, for instance, would need to be 13.6 times taller than a mercury barometer to obtain the same pressure difference. This is because mercury is 13.6 times more dense than water .
Is mercury expensive or cheap?
Mercury is cheap because the company offers a wide variety of discounts that almost anyone can get, including discounts for signing documents electronically and setting up autopay. Mercury ranked 7th overall in WalletHub’s cheap car insurance study of more than 40 major insurers.
What fluid is used in a manometer?
Most of the case, for gauge pressure measurements, mercury is widely used as manometric fluid because it has non-evaporating quality under normal conditions, sharp meniscus and stable density. For some pressure differences and low-level vacuum, water can be considered as working fluid in the manometer.
What fluid goes in a manometer?
The open-end manometer (Fig. 4.4a) is a glass tube, usually U-shaped, filled with the manometer fluid (mercury or oil) (see Section 3.2).
What is the disadvantage of manometer?
No fixed reference is available. In manometer, the error is introduced due to condensation . It has no over range protection . The manometer has a poor dynamic response.
Where do we use manometer?
– Typical manometer applications include measuring pipe fluid flows, HVAC system pressure, and gas pressure . – Typical manometer liquids are mercury, water, and light oils. – One end of a U-tube manometer is connected to an unknown pressure while the other end is left exposed to the atmospheric pressure.
Can mercury used in hydrometer?
Hydrometers are often used in cooking, especially in beer and wine making. They are typically made of glass and consist of a cylindrical stem and weighted bulb, which makes the device float upright in the liquid solution. Historically, elemental mercury was used in hydrometers as a weight.
Why is water not used in a barometer?
water cannot be used as barometric liquid because it’s density is lower than Mercury . water’s density is 1000 gram per cubic meter. hence it requires a barometer whose height is around 11 meters.
Does a hydrometer have mercury in it?
Identifying pressure and other gauges may contain mercury
sphygmomanometers (blood pressure measuring devices), hydrometers (used to measure the specific gravity of fluids in maple sugaring, wine and beer making, etc.)
